Advances in Parkinson’s Disease
Parkinson’s disease (PD) affects nearly one million Americans, though this number may be underestimated. The disease is an age-related progressive motor disorder that affects the nervous system. Symptoms usually begin gradually and worsen over time.
While the most recognized symptoms are motor, including tremors, rigidity or muscle stiffness, bradykinesia, which means small or slow movements, and gait and posture problems, there are nonmotor symptoms for Parkinson’s disease. Non-motor symptoms can include cognitive dysfunction, sleep disturbance, low blood pressure, constipation, and depression and anxiety. Over the past 10 years, we have learned more about these nonmotor symptoms and their treatment.
For instance, we now understand that PD is associated with a specific pattern of cognitive dysfunction related to flexibility of thought, such as motor planning and changing motor plans. For example, people with PD can experience difficulty initiating a movement called “freezing.” It may be helpful to understand that the difficulty with movement initiation is likely related to the cue or signal to move.
The internal, thought-based cueing system, which people without PD take for granted, can be disrupted, resulting in freezing. But the external cueing system, like the visual cue of a traffic light switching from red to green or the auditory signal of the starting gun at a track meet, is still intact. This means freezing can be reduced using external cues. The cue can be as simple as placing a hand on the shoulder of a spouse with PD. There are also commercially available products, such as walkers equipped with a laser that can provide a visual cue at floor level to reduce freezing of gait.
Another cognitive issue in Parkinson’s disease relates to patient self-awareness. People with PD often do not realize that they are exhibiting signs of the disease. Friends, family and coworkers may also not recognize the signs of PD, leading to underdiagnosis, especially in underserved communities. Diagnosis is critical in Parkinson’s disease. Unlike most age-related neurodegenerative diseases, medications can help with PD symptoms, significantly improving quality of life for many years. Innovative improvements on these medications are also working their way to the marketplace.
In addition, while there are currently no disease-modifying treatments to stop or slow the progression of the disease, scientists are working hard to find one. For example, in February of 2023, a group at the University of Queensland Brain Institute announced findings from a genetic study showing that a gene associated with increased PD risk also impairs signaling for normal cellular debris removal. Cell debris is organic waste left behind when a cell dies. This study suggests that restoring debris removal may help fight the disease.
Also under study for treating PD are antioxidants, anti-inflammatory agents and medications such as calcium channel blockers traditionally used to lower blood pressure, the class of diabetes medication called glucagon-like peptide-1 agonists, and tyrosine kinases currently used to target cancer cells.
A tremendous effort is being exerted to understand the genetic basis of Parkinson’s disease; however, the task is complicated: While we have learned a lot about the genetics of PD in the last 10 years, still, about 90% of people with PD have no known genetic link. Parkinson’s disease without a genetic link is called “sporadic,” or occurs at irregular intervals, and the children of sporadic PD patients are unlikely to get the disease. Furthermore, while genetic variations that increase the risk of PD have been identified, most people with these variations do not get the disease.
To untangle the genetic puzzle of PD, one team of scientists is collecting genetic samples from across the globe. We believe that this collection of a diverse sample of data will help us unlock the genetic causes of PD in part because the disease occurs at different frequencies in different groups. Unlike Alzheimer’s disease, men are more likely than women to get Parkinson’s disease, and Caucasian individuals are at higher risk than African American individuals.
Understanding why some groups are at higher or lower risk than others will provide important insight into the mechanism of the disease. However, 90% of genetics studies related to Parkinson’s disease have involved populations of European ancestry, while the genetic impact on PD susceptibility in Black and African American individuals is not well understood.
Fortunately, there is a new local opportunity to contribute to the cure. LSU Health Shreveport has partnered with The Michael J. Fox Foundation for Parkinson’s Research (MJFF) to become one of six sites participating in the Black and African American Connections to Parkinson’s Disease (BLAAC-PD) study, a project of the Global Parkinson’s Genetics Program (GP2) and the Aligning Science Across Parkinson’s (ASAP) initiative. Also participating in the study is the Parkinson’s Disease Foundation. The network subserves a global program to conduct scientific research and analysis to identify genetic links to Parkinson’s disease.
LSU Health Shreveport is currently recruiting volunteers to participate in the BLAAC-PD study. People who meet the following criteria are eligible to be a part of this study: • Diagnosed with Parkinson’s disease (any race) OR • Identify as Black or African American • Age 18 or older • With or without Parkinson’s disease There is no cost to participate, and participants will be compensated. To learn more or to participate, contact Dr. Elizabeth Disbrow and her team at The Bridge, a resource center associated with the LSU Health Shreveport Center for Brain Health, at 851 Olive St. (318) 656-4800, CBHResearch01@lsuhs.edu or visit Parkinson.org/PDGENEration or blaacpd.org.